Development and characterization of microencapsulation systems for bioactive ingredients of interest in the development of functional foods
- Autores: Laura Gómez Gómez-Mascaraque
- Directores de la Tesis: Amparo Lopez Rubio (dir. tes.), Pau Talens Oliag (tut. tes.)
- Lectura: En la Universitat Politècnica de València ( España ) en 2017
- Idioma: español
- Tribunal Calificador de la Tesis: Alexandra Muñoz Bonilla (presid.), María Consuelo González Martínez (secret.), Sandra Martha Domenek Aichernig (voc.)
- Programa de doctorado: Programa de Doctorado en Ciencia, Tecnología y Gestión Alimentaria por la Universitat Politècnica de València
- Materias:
- Enlaces
- Tesis en acceso abierto en: RiuNet
- Resumen
The aim of the present work was to design and characterize novel encapsulation structures of interest in the development of functional foods. For this purpose, various biopolymer-based microencapsulation structures were obtained through different processing technologies, with an emphasis on electrospraying as an advantageous alternative to conventional microencapsulation techniques.
Firstly, novel microencapsulation structures were produced from aqueous solutions and in mild conditions by electrospraying, using different biopolymers as encapsulation matrices. For this purpose, the processing conditions were optimized and the relationship between the feed solution properties and the morphology of the electrosprayed materials was studied.
The developed microstructures were then used to microencapsulate model bioactive ingredients with different properties, including hydrophilic molecules, hydrophobic compounds and probiotic microorganisms. For the hydrophobic ingredients, different strategies were evaluated in order to disperse them within the aqueous biopolymer solutions, such as the preparation of emulsions and liposome dispersions prior to electrospraying. An in-line setup for the continuous mixing of liposomes with the biopolymer and their subsequent hybrid capsule formation was also developed by combining microfluidic and electrospraying technologies. For the probiotic microorganisms, the convenience of preparing the feed suspensions from fresh culture or freeze-dried bacteria, as well as the impact of adding a surfactant and a prebiotic carbohydrate to the formulation, were also evaluated.
The performance of the proposed encapsulation systems was evaluated in terms of microencapsulation efficiency, stabilization of the bioactive ingredients against degradation under detrimental conditions and/or their impact on the bioaccessibility of the microencapsulated ingredients after in-vitro digestion.
Spray-drying was also used to microencapsulate some of the bioactive ingredients, in order to compare the results obtained through electrospraying with a more conventional encapsulation technique and using different encapsulation matrices.
Additionally, a novel concept of bio-inspired encapsulation was proposed in this thesis: the potential of intact plant cells isolated from potato tubers to bind phenolic compounds was explored, and the impact of starch gelatinization on the loading capacity of these proposed encapsulation vehicles was also assessed.
Finally, the impact of microencapsulation in real food systems was also studied. Yoghurts and biscuits were enriched with a peptide hydrolysate and a green tea extract, respectively, and the stabilization effect of the protective matrices during food manufacturing was assessed. The consumers' acceptability of the enriched biscuits was also studied.
